BlockRandGauss.hpp
3.2 KB
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
/****************************************************************************
*
* Copyright (C) 2012 PX4 Development Team. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
* 3. Neither the name PX4 nor the names of its contributors may be
* used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
* OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
* AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
****************************************************************************/
/**
* @file blocks.h
*
* Controller library code
*/
#pragma once
#include <px4_platform_common/defines.h>
#include <assert.h>
#include <time.h>
#include <stdlib.h>
#include <math.h>
#include <mathlib/math/test/test.hpp>
#include <mathlib/math/filter/LowPassFilter2p.hpp>
#include "block/Block.hpp"
#include "block/BlockParam.hpp"
#include "matrix/math.hpp"
namespace control
{
class __EXPORT BlockRandGauss: public Block
{
public:
// methods
BlockRandGauss(SuperBlock *parent,
const char *name) :
Block(parent, name),
_mean(this, "MEAN"),
_stdDev(this, "DEV")
{
// seed should be initialized somewhere
// in main program for all calls to rand
// XXX currently in nuttx if you seed to 0, rand breaks
}
virtual ~BlockRandGauss() = default;
float update()
{
static float V1, V2, S;
static int phase = 0;
float X;
if (phase == 0) {
do {
float U1 = static_cast<float>(rand()) / static_cast<float>(RAND_MAX);
float U2 = static_cast<float>(rand()) / static_cast<float>(RAND_MAX);
V1 = 2 * U1 - 1;
V2 = 2 * U2 - 1;
S = V1 * V1 + V2 * V2;
} while (S >= 1 || fabsf(S) < 1e-8f);
X = V1 * float(sqrtf(-2 * float(logf(S)) / S));
} else {
X = V2 * float(sqrtf(-2 * float(logf(S)) / S));
}
phase = 1 - phase;
return X * getStdDev() + getMean();
}
// accessors
float getMean() { return _mean.get(); }
float getStdDev() { return _stdDev.get(); }
private:
// attributes
control::BlockParamFloat _mean;
control::BlockParamFloat _stdDev;
};
} // namespace control